1. Field of the Invention
The present invention relates, in general, to deburring tools and, in particular, to a deburring tool having a replaceable blade.
2. Description of the Related Art
A deburring tool is generally employed to remove burrs left on an edge defined by a passage cut or drilled through a work-piece, such as a valve body or the like, made of metal or other material and to cut a chamfer on the edge. Deburring tools known in the related art are respectively disclosed in U.S. Pat. No. 4,086,018 issued to Robinson et al. on Apr. 25, 1978 for a pin-type deburring tool having a replaceable cutting head; U.S. Pat. No. 4,147,463 issued to Robinson on Apr. 3, 1979 for an adjustable-position deburring tool having a replaceable and adjustable-position cutting head; U.S. Pat. No. 5,358,363 issued to Robinson on Oct. 25, 1994 for a lockable deburring tool having a replaceable and adjustable-position cutting head; and U.S. Pat. No. 5,501,554 issued to Robinson et al. on Mar. 26, 1996 for another lockable deburring tool having a replaceable and adjustable-position cutting head.
One type of a deburring tool generally includes an elongated cylindrical body, or arbor (or pilot), formed with a recess for receiving a blade. The recess extends a fixed distance into the arbor and typically has two closed ends. The recess defines a pair of opposed, flat surfaces disposed in spaced, parallel relationship with respect to one another. A unitary blade is received in the recess and includes a cutting head with an integral, elongated, flat, resilient blade extending therefrom. The blade is removably mounted in the arbor such that a point is defined about which the blade can pivot.
More specifically, it is well known in the related art to mount the blade in the arbor by a pair of pins spaced from each other relative the longitudinal axis of the blade and extend transversely of the blade through the recess and a pair of correspondingly spaced openings defined in the blade. One of the pins may be a roll pin that extends through one of the openings to define the pivot point. The other pin extends through the other opening defined at the end of the blade opposite the cutting head and holds this end in non-pivotal relationship with the arbor with the cutting head projecting from the recess for engaging a work-piece. The portion of the blade extending from the roll pin toward the cutting head is resiliently yieldable to permit the cutting head to move inwardly with respect to the recess during a deburring operation. Each of the arbor and blade may be removed and replaced by removing the pins. A deburring tool of this type is known in the related art as a pin-type or fixed-position deburring tool having a fixed-position cutting head.
It is also well known in the related art to mount the blade in the arbor by securing the end of the blade defined opposite the cutting head to the arbor in such a manner that not only is a portion of the blade yieldable to permit the cutting head to move inwardly with respect to the recess, as with the fixed-position cutting head, but also the cutting head is biased to an operable position extending from the recess. More particularly, the blade can be selectively pivotally adjusted with respect to the arbor to, in turn, adjust the unstressed position of the cutting head with respect to the recess. In this case, a pin is mounted in and extends transversely of the arbor through the recess and the blade, and an adjustable screw is threadedly mounted in and extends transversely of the arbor at a location spaced from the pin with the longitudinal axis of the screw extending perpendicularly to the longitudinal axis of the pin. The blade is connected with the screw in such a manner that rotation of the screw in the arbor pivotally adjusts the blade to adjust the unstressed position of the cutting head with respect to the recess. In other words, adjustment of the screw adjusts the pivot of the blade about the pin, thereby adjusting the position of the cutting head relative to the recess prior to any deburring activity. Each of the arbor and blade may be removed and replaced by removing the pin and screw. A deburring tool of this type is known in the related art as an adjustable-position deburring tool having an adjustable-position cutting head.
It is also well known in the related art to mount the blade in the arbor and then to receive and mount the arbor in an assembly holder. In this case, the arbor includes a head portion disposed at one end of the arbor, and the recess extends from the head portion to the end of the arbor defined opposite the head portion. Furthermore, the blade is mounted between the pair of opposed, flat surfaces defined by the recess and the arbor. The assembly holder has a central passage extending longitudinally through the assembly holder and adapted to receive the arbor. The central passage holds in position the pair of opposed, flat surfaces to frictionally clamp the blade between the pair of opposed, flat surfaces. The assembly holder also has an aperture extending transversely of the central passage and adapted to receive a screw to fixedly mount the arbor and blade within the assembly holder. In this way, the blade can be mounted in the recess and held in place by the assembly holder. The assembly holder and, thus, arbor and blade may be removed and replaced by removing the screw. This type of deburring tool is not adjustably positionable, may be used to deburr a passage having a relatively small diameter, and, in this case, has been referred to as a micro deburring tool.
It is also well known in the related art to mount the blade in the arbor by another method using an adjustable screw and a pivot member. In this method, the screw is threadedly mounted in and transversely of the arbor for fixedly engaging a terminal portion of the blade. The pivot member extends through and transversely of the recess and blade to define the pivot point about which the blade can pivot and includes a non-threaded, hemispherical portion having at least one flat face. The blade defines an open-arced, partially circumferential slot that, with the blade, defines a flat at one end of the partial circumference. The hemispherical portion is received in the slot and adapted to rotate therewithin until the flat face of the hemispherical portion comes into abutting engagement with the flat presented by the blade and slot to lock the blade within the arbor while permitting the blade to pivot about the pivot member. When it is time to change the blade, the flat face is rotated out of engagement with the flat by rotation of the pivot member, the screw and pivot member are removed, and the blade is lifted from the arbor. The pivot member may be rotated by using an Allen wrench, a regular screwdriver, a Phillips-head screwdriver, or any other type of conventional tool while the arbor remains mounted in a machine used to drive the deburring tool. This type of deburring tool is known in the related art as a lockable deburring tool and one also with an adjustable-position cutting head.
The blades, in general, may be stamped from steel stock, with each blade being drilled with the openings or slot to accept the pins or pivot member, respectively, and then heat-treated to increase its hardness. The recess may be formed using a milling or grinding tool or a wire EDM as well. There are usually two to six blade changes before the arbor needs to be replaced.
While the deburring tools of the related art generally perform satisfactorily, they are not without their respective problems. For example, to replace a worn-out blade of some of the deburring tools of the related art, an operator must remove the deburring tool from a rotatable tool holder or chuck of a drive motor, drive the pins completely through the corresponding openings in the blade and out of the arbor, remove the blade from the arbor, replace the blade with a new blade, and then drive the pins back into the arbor and through the corresponding openings in the new blade. This process is inconvenient and time-consuming and, therefore, expensive. In addition to this problem, the roll pin has a limited useful life of approximately one to three cutting-tool changes. Even with the deburring tool of the related art having a blade that can be replaced without need to drive pins in and out of the arbor, the operator must still rotate the screw and pivot member with a tool such that the worn-out blade can slide out of the arbor and the new blade can slide into the arbor.
Thus, there is a need in the related art for a more convenient, cost-effective deburring tool that is made using high-quality tool steel. More specifically, there is a need in the related art for a deburring tool that makes changing a worn-out blade thereof easier, faster, and tool-free and, thereby, reduces down-time in any deburring operation to increase the efficiency thereof.